Nina I. Pavlenko

Chemistry of vinylidene complexes. XIII. The reaction between Cp(CO)2MnPt(μ-CCHPh)(η2-dppm) and Fe2(CO)9: simultaneous formation of the μ3-vinylidene MnFePt and μ4-vinylidene PtFe3 clusters. Crystal structure of (η5-C5H5)MnFePt(μ3-CCHPh)(CO)6[η1-Ph2PCH2P(O)Ph2] ☆ ☆☆

Abstract The reaction between [Cp(CO)2MnPt(μ-CCHPh)(η2-dppm)] 2 (1) and [Fe2(CO)9] gives heterometallic MnFePt and PtFe3 vinylidene clusters 2–4, in which diphosphine ligands are coordinated to metal cores in three different modes. In [(η2-dppm)PtFe3(μ4-CCHPh)(CO)9] (2) the Pt atom is chelated by dppm while in [CpMnFePt(μ3-CCHPh)(μ-dppm)(CO)5] (3) dppm bridges the Pt–Fe bond. Complex 3 was shown to exist in two isomeric forms. The novel complex {CpMnFePt(μ3-CCHPh)(CO)6[η1-Ph2PCH2P(O)Ph2]} (4), characterized by X-ray diffraction study, possesses a trimetallic chain core. The diphosphine ligand in 4 links to platinum by only one of phosphorus atoms whereas the second P atom is uncoordinated and oxidized to the phosphineoxide group.

Chemistry of vinylidene complexes XI. Synthesis of trinuclear MnFePt complexes by means of consecutive assembling out of mono- and dimetal vinylidene precursors

The dimetal μ-vinylidene complexes Cp(CO)2MnPt(μ-C = CHPh)L2 (L = tert.-phosphine or -phosphite), which have been obtained by coupling of the mononuclear complex Cp(CO)2Mn=C=CHPh and unsaturated PtL2 unit, add smoothly the Fe(CO)4 moiety to produce trimetal MnFePt compounds. The μ3-vinylidene cluster CpMnFePt(μ3-C=CHPh)(CO)6(PPh3) was prepared in quantitative yields from the reactions of Cp(CO)2MnPt(μ-C=CHPh)(PPh3)L (L = PPh3 or CO) with Fe2(CO)9 in benzene at 20 °C. The phosphite-substituted complexes Cp(CO)2Mnpt(μ-C=CHPh)L2 (L = P(OEt)3 or P(OPri)3) react under analogous conditions with Fe2(CO)9 to give mixtures (2:3) of the penta- and hexacarbonyl clusters, CpMnFePt(μ3-C = CHPh)(CO)5L2 and CpMnFePt(μ3-C = CHPh)(CO)6L, respectively. The similar reaction of the dimetal complex Cp(CO)2MnPt(μ-C = CHPh)(dppm), in which the Pt atom is chelated by dppm = Ph2PCH2PPhPin2 ligand, gives only a 15% yield of the analogous trimetal μ3-vinylidene hexacarbonyl product CpMnFePt(μ3-C = CHPh)(CO)(dppm), but the major product (40%) is the tetranuclear μ4-vinylidene cluster (dppm)PtFe3(μ4-C = CHPh)(CO)9. The IR and 1H, 13C and 31P NMR data for the new complexes are reported and discussed.

Chemistry of vinylidene complexes XII. Transmetalation of the μ-vinylidene ligand in the reaction of Cp(CO)2MnPt(μ-CCHPh)(dppp) with Fe2(CO)9. Formation of new PtFe, PtFe2 and PtFe3 complexes

Abstract The reaction between [Fe 2 (CO) 9 ] and [Cp(CO) 2 MnPt(μ-C CHPh)(dppp)] ( 1 ), where dppp is Ph 2 P(CH 2 ) 3 PPh 2 , proceeds stepwise, initially through transmetalation of the bridging vinylidene ligand, i.e. with replacement of the [Mn(CO) 2 Cp] fragment by the [Fe(CO) 4 ] group, to produce the novel binuclear μ-vinylidene complex [(dppp)PtFe(μ-C CHPh)(CO) 4 ] ( 2 ), which reacts further with [Fe 2 (CO) 9 ] to yield the tetranuclear cluster [(dppp)PtFe 3 (μ 4 -C CHPh)(CO) 9 ] ( 3 ) and the trinuclear complex [(dppp)PtFe 2 (CO) 8 ] ( 4 ). The IR and 1 H, 13 C and 31 P NMR data for the new complexes are reported and discussed.

Infrared study of transformation of a terminal carbonyl ligand into a bridging one in the MnPt and MnPd μ-vinylidene complexes

Abstract The IR study of a series of heterometallic vinylidene-bridged complexes CP(CO) 2 MnM( μ -C = CHPh)LL′, where M = Pt or Pd, L and L′ = CO, tert -phosphites, PPh 3 , Ph 2 P(CH 2 ) n PPh 2 , n = 1–3, demonstrated the existence of a gradual transformation of one of the terminal CO groups at the Mn atom into bridging one spanning the Mn-M bond, which goes through the intermediate semi-bridging form and is induced by the electron-donating capacities of ligands L and L′ at the M atom.

Diadamantylation of dihydric phenols and their derivatives

Dihydric phenols and their monomethyl ethers were converted into diadamantyl derivatives by the reaction with 1-adamantanol in trifluoroacetic acid.

Electrochemical study of heteronuclear complex [Cp(CO)2MnCu(μ-C=CHPh)(μ-Cl)]2

The electrochemical behavior of the heteronuclear dimeric vinylidene complex [Cp(CO)2MnCu(μ-C=CHPh)(μ-Cl)]2 (I) is studied using polarography, cyclic voltammetry, and controlled-potential electrolysis on mercury and platinum electrodes in acetonitrile. The dimer is reduced in two two-electron stages: at the first stage, metal-halogen bonds are broken and binuclear monomers [Cp(CO)2MnCu(μ-C=CHPh)(Cl)]− are formed; at the second stage, mononuclear manganese complexes Cp(CO)2Mn=C=CHPh, metallic copper, and chloride ions are formed. The two-electron oxidation of dimer [Cp(CO)2MnCu(μ-C=CHPh)(μ-Cl)]2 also results in the formation of binuclear monomers, which decompose to complex Cp(CO)2Mn=C=CHPh, Cu2+ ions, and Cl− ions.

Adamantylation of polysubstituted arenes in trifluoroacetic acid

A reaction of 2,3-xylenol, 2,3-dichlorophenol, and 1,3-disubstituted benzenes with 1-adamantanol in trifluoroacetic acid leads to the corresponding monoand diadamantylated products.

Elemental Composition and Structural Peculiarities of Humic Acids in Bog Waters of Taiga Zone

Results of a complex studying the preparations of humic acids from bog waters by methods of IR spectroscopy, nuclear magnetic resonance and electronic paramagnetic resonance have been considered in the paper. Properties of humic acids are evaluated according to the elemental composition. Commonality and character of varying the composition of humic acids under forest oligotrophic and mesotrophic bogs are discussed hereaswell. The opinion about probable mechanisms of humic acid synthesis in bogs of different genesis is suggested.

Electrochemical Study of a Heterobinuclear pyridylvinylidene Complex Cp(CO)2Fe [μ-C=CH(2-C5H4N)]PdI

Victor V. Verpekin*a, Galina V. Burmakinaa,b, Dmitry V. Zimonina, Nina I. Pavlenkoa, Oleg. V. Semeikinc and Arkadii Z. Kreindlinc aInstitute of Chemistry and Chemical Technology SB RAS FRC “Krasnoyarsk Science Center SB RAS” 50/24 Akademgorodok, Krasnoyarsk, 660036, Russia bSiberian Federal University 79 Svobodny, Krasnoyarsk, 660041, Russia cA.N. Nesmeyanov Institute of Organoelement Compounds RAS 28 Vavilova Str., Moscow, 119991, Russia

Synthesis of a Polyconjugated Polymer by Aldol Condensation of 2,5-Diformylfuran and Acetone

Pioneer synthesis of the product of aldol polycondensation between 2,5-diformylfuran and acetone is presented. The synthesis was accomplished by a direct reaction of diformylfuran and acetone in dimethyl sulfoxide with addition of aqueous sodium hydroxide as a catalyst. The fact of the aldol condensation occurrence and formation of the polyconjugated oligomers in this system is confirmed by 1H nuclear magnetic resonance and molecular absorption spectroscopy. Cannizzaro reaction plays a significant side process role in the studied system, leading to the loss of diformylfuran’s aldehyde groups and their inability to participate in polymer chain growth. A solid polymeric product of brown color was isolated with the yield of 28 % based on the initial diformylfuran. The solid product is insoluble (judging by the lack of coloration in liquid) in various tested solvents: water, 1,4-dioxane, dimethyl sulfoxide, acetone, chloroform, or 1,2-dichloroethane with trifluoroacetic acid mixed in different proportions. The presence of polyconjugated chains in the solid product is confirmed by electron spin resonance spectroscopy.